Clamping device.



G. J. LANDIN. OLAMPING DEVICE.

APPLIOATION puma JUNE 6, 1912.

Patented Dec. 2, 1913.

' Z012 mass-65'.

CARL J. LANDIN, OF BOSTON, MASSACHUSETTS.

CLAMPING DEVICE.

Specification of Letters Patent.

Patented Dec. 2,1913.

Application filed June 6, 1912. Serial No. 702,062.

ToaZZ whom it may concern Be it known that I, CARL J. LANDIN, a citizen of the United States, residing in Boston, county of Suffolk, and State of Massachusetts, have invented an Improvement in Clamping Devices, of which the following description, in connection with the accom panying drawings, is a specification, like letters on the drawings representing like parts.

This invention relates to a double clamp, especially adapted among other uses, to be employed as an adjusting device for the cords of incandescent electric lamps.

The invention has for its object to provide a simple, efiicient and inexpensive device for the purpose specified.

Figure 1 is a perspective view of a double clamp embodying this invention. Fig. 2, a plan view of the clamp shown in Fig. 1, showing one of the members in its open position by dotted lines. Fig. 3, a horizontal longitudinal section of the clamp shown in Fig. 2. Fig. 4, a plan view of one of the clamping members. Fig. 5, an end view of the clamp shown in Fig. 2, and Fig. 6, a detail to be referred to.

Referring to the drawings, 10, 12 repre sent the members of a double clamp embodying this invention.

The members 10, 12, may be made of wood, porcelain, or other suitable material, and said members are provided with in clined or beveled inner surfaces 13, 14, and are yieldingly connected together bet-ween their ends by a suitable spring, which in the present instance, is shown as a helical spring 15 located in a socket 16, preferably at the center of one member, as 12, and having its free end connected by a pin or rod 17 with the other member 10, which is also provided with a socket 18 for the reception of the head 19 of said pin or rod.

The spring 15 acts to hold the two members normally in contact and exerts a suflicient pressure upon a cord 20 or other article placed between them to firmly hold the same.

The members 10, 12 herein shown are provided on their inner faces on opposite sides of the center with grooves 21, 22, which are arranged in said members so that the grooves 21 in one member register with the grooves 22 in the other, and said grooves are made slightly smaller than the cord 20, so that the latter will be firmly clamped between the members.

The inclined inner surfaces at the opposite ends of the members enables the ends of said members to be brought nearer together, so as to open up the members at the end opposite to that to which pressure is applied, in which case the members pivot on their inner surfaces between the center of the members and the inclined ends pressed upon.

If desired, the members may be provided on their inner surfaces with well defined pivot points, and in the present instance, the member 10 is provided atone end with a projection 24, which enters a groove or recess 25 in the same end of the other member 12, and the opposite end of the member 10 may be provided with a groove or recess 26 into which extends a projection 27 on the member 12.

By reference to Figs. 1, 2 and 3, it will be seen that by applying pressure to the right hand end of the members, as by the thumb and finger of the operator, indicated by dotted lines, Fig. l, the left hand end of the members are separated so as to allow a portion of the cord 20 to be placed between the members and into one of the grooves 21 or 22, after which the pressure of the hand is removed and the spring restores the members to their normal position with the portion of the cord firmly held by the clamping members. The operator then presses upon the left hand end of the members, so as to open up the right hand end and allow another portion of the cord to be placed in one of the grooves 21 or 22 on the opposite side of the center, and when the cord is properly entered, the pressure is removed and the members are restored to their normal or parallel position by the spring, with the cord firmly held on opposite sides of the longitudinal center of the clamp.

When it is desired to adjust the cord, it is only necessary to open one end of the clamp bypressure applied to the other end, and move the cord up or down, and when properly adjusted the pressure is removed and the open end of the clamp is closed by the spring.

It will he observed that when the pressure is applied to the right hand end of the members to open the opposite end, the pivot for the said members is at the right of the longitudinal center of the said members, namely, the projection 24, and that when pressure is applied to the left hand end of said members to open the right hand end of the clamp, the pivot for the members is at the left of the longitudinal center, namely, the projection 27.

I have herein described the double clamp as an adjuster for the cord of an incandescent electric lamp, but it is not desired to limit the invention to this particular use.

In the present instance, the spring 15 is located near the longitudinal center of the members, and as aresult both ends grip with equal pressure or strength, but the grip of said ends may be varied by changing the location of the pivot projections or by changing the position of the spring.

It is preferred to provide the members with grooves on their inner faces, but it is not desired to limit the invention in this respect, as said grooves in some instances may be omitted. Furthermore, it is not desired to limit the invention to the particular form of spring herein shown.

In the present instance, I have shown one construction of clamp embodying this inven tion, but it is not desired to limit the invention to the particular construction shown.

While it is preferred to provide each member with an inclined surface at each end, it is not desired to limit the invention in this respect, as good results may be obtained by providing each member with an inclined surface at one end only and arranging the members so that the inclined surfaces are at opposite ends of the clamp, as for instance, by omitting the inclined surfaces 1a of both members.

Claims:

1. A double clamp of the character described, comprising two members bodily movable toward and from each other and having at their ends inclined inner surfaces of substantial length to leave a substantially wide opening between the extreme ends of said inclined surfaces at both ends of the clamp, and provided between their ends with recesses on their inner surfaces, and a spring connecting the said members together and connected therewith to normally hold the said members in their closed position and to permit one end of one member to be moved bodily away from the same end of the other member for the passage of a cord between them, while a cord or other device is clamped between the opposite ends of said members.

2. A double clamp of the character described, comprising two members bodily movable toward and from each other and having at their ends inclined inner surfaces of substantial length to leave a substantially wide opening between the extreme ends of said inclined surfaces at both ends of the clamp, and provided between their ends with recesses on their inner surfaces, one of said members having a recess, and the other member a projection at each end which extends into said recess and forms a pivot point, and a spring connecting the said members together and connected therewith to normally hold the said members in their closed position and to permit one end of one member to be moved bodily away from the same end of the other member for the passage of a cord between them while acord or other device is clamped between the opposite ends of said members.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CARL J. LANDIN.

Witnesses JAS. H. CHURCHILL, J. MURPHY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). 'G. 

